DTC P0125 - ECT Sensor Excessive Time To Reach Closed Loop: Notes

WARNING: This page is about a different car, the 1998 Pontiac Bonneville, 1998 Oldsmobile Regency, 1998 Oldsmobile LSS, 1998 Oldsmobile Eighty-Eight, and 1998 Buick LeSabre. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: For circuit reference, see WIRING DIAGRAMS article.

While engine is warming, PCM reads Engine Coolant Temperature (ECT) sensor to determine how long it takes coolant to reach temperature required for closed loop operation. PCM compares actual time required to a predetermined time.

Conditions required to set DTC are:

No ECT or IAT DTCs are set.
Vehicle speed greater than 5 MPH.
IAT greater than 50°F (10°C).
ECT greater than 32°F (0°C).
Start-up ECT less than 70°F (21°C).
Closed loop operation temperature of 68°F (20°C) not reached within 2 minutes of start-up.